大型混流式水轮机转轮用铸钢件夹杂缺陷预测与工艺优化  

Slag Inclusion Defects Prediction and Process Optimization of Large Francis Turbine Runner Steel Casting

作　　者：沈旭[1] 鲁文涛 殷亚军[1] 计效园[1] 万鹏[1] 周建新[1] SHEN Xu;LU Wen-tao;YIN Ya-jun;JI Xiao-yuan;WAN Peng;ZHOU Jian-xin(State Key Laboratory of Material Processing and Die & Mould Technology,Huazhong University of Science and Technology,Changsha Hunan 430074,China)

机构地区：[1]华中科技大学材料成形与模具技术国家重点实验室,湖南长沙430074

出　　处：《铸造设备与工艺》2018年第6期8-12,27,共6页Foundry Equipment & Technology

基　　金：国家自然科学基金面上项目(项目号:51775205);材料成形与模具技术国家重点实验室重点自主研究项目(数字化智能化铸造技术及应用)

摘　　要：水轮机转轮用铸钢件是大型混流式水轮机的关键部件,是水流动能转化为电能的主要运动装置,如何高效、高质地制造水轮机转轮用铸钢件是高效、长效发电的基础。本文以数值模拟为突破点,对水轮机转轮用部件(上冠和下环)铸造过程的典型缺陷进行预测,结合缺陷结果对水轮机部件分别进行工艺优化,以期获得良好的铸件。分析水轮机转轮用下环铸钢件的典型缺陷,确定了夹杂为其主要缺陷。建立了夹杂粒子运动轨迹预测模型,对原始工艺水轮机转轮用下环铸钢件进行充型过程流动分析及夹杂粒子运动轨迹预测,基于模拟分析手段,对下环铸钢件进行工艺优化,对夹杂缺陷的消除与转移具有良好的效果。通过对下环、上冠两部分铸件的铸造工艺分析优化,可以获得质量优良的铸件,为后续焊接成整个转轮提供了强有力的方案支撑,对其他水轮机转轮用铸钢件提供技术支持。The turbine runner castings are the key parts of the large-scale Francis turbines,which is the main motion device for converting the kinetic energy into electric energy.How to produce turbine runner with high-efficiency,high quality is the foundation of efficient and long-term power generation.This paper takes the numerical simulation as the breakthrough point,and the typical defects of the component(upper crown and lower ring)casting process of the turbine runner is predicted.Combined with the defect results,the turbine were individually optimized to obtain a good quality castings for welding.The typical defects of the lower ring castings for turbine runners are analyzed and inclusions were identified as their main defects-Subsequently,a trajectory prediction model for inclusion particles was established.The flow analysis of the filling process and the trajectory prediction of inclusion particles were performed on the lower ring castings of the original process.The lower ring casting process is optimized based on the simulation analysis method,which has a good effect on the elimination and transfer of inclusion defects.Through the analysis and optimization of the casting process of the lower ring and the upper crown,the castings with good quality can be obtained.lt provides powerful program support for the subsequent welding to complete Francis turbine and provides technical support for runner castings for other turbines.

关 键 词：缺陷预测 工艺优化 铸钢件 水轮机转轮 

分 类 号：TG244[金属学及工艺—铸造]